1. Field of the Invention
This invention relates to a vacuum box for collecting small particles such as wood chips or shavings but may also be utilized for the collection of dental scrapings and dust or small metal fragments resulting from the fabrication of gold products or the like.
2. Description of the Prior Art
In the carving field, there are presently existing a number of vacuum boxes which are intended to collect small wood shavings or sawdust in order to reduce the contamination of the surrounding area or to the air.
One such vacuum box utilizes a hooded cofiguration with an exposed filter in which air is drawn through the filter for the collection of the dust thereon. While such a configuration may prevent general disposition of the dust in the air, the exposed side of the filter could inadvertently become a source of sawdust if it is accidently dislodged or removed prior to proper disposition. Additionally, if the pieces of wood produced by the carving are relatively large, there is no guarantee that they will properly adhere to the filter surface.
Another large vacuum box used in the carving field includes a large evacuated container in which the entire lower region of the container is intended for the collection of wood particles or dust. A working surface for this large vacuum box includes a screen for pulling the particles into the interior of the vacuum box. Once the particles are inside the vacuum box, they may fall to the enlarged lower region for eventual removal. Air inside the vacuum box is evacuated through an upper region of the box and discharged out the rear of the vacuum box. However, collection of the particles in this manner can be quite dangerous. Collection of wood particles in the lower region of such a large box has resulted in a fire hazard since small sparks entering the screened working area could deposit in the collection of dust particles in the lower region of the large vacuum box. Since such a spark could create a fire in the lower region of the large vacuum box, the operator may not even be aware of its existence until the fire is out of control.
U.S. Pat. No. 4,047,913 discloses a dust collector for dental technicians. However, the configuration disclosed therein, while appearing similar to that of the present invention, includes a relatively complicated double-screened area which is exposed to the operator. Air passing through the screen goes through a fan which ultimately discharges to yet another screen configuration for the collection of fine dust particles. However, this configuration, similar to that mentioned above, allows major particles to be left on an exposed surface for possible loss to the atmosphere or surroundings. Still further, including a major filter after the fan leaves the fan exposed to small particles which are being forced therethrough. If such a device was used in the carving field, the collection of sawdust around the motor of the fan could, as mentioned above, result in a fire hazard.
U.S. Pat. No. 2,602,417 discloses a dusting cabinet used in the preparation of printing plates or the like. Again, such a configuration employs a large cabinet and causes the particles or substance therein to be drawn to a lower region thereof. Collection of the lower region in filters could again, if used, for example, in the carving field, result in a collection of dust subject to combustion. Collection in the lower region in this manner would make discovery by the operator less likely and eventual suppression of the combustion more difficult.
A number of other patents disclose more complicated exhaust or collecting devices which have particular application in specific work-related environments. U.S. Pat. No. 1,902,211 discloses a hair collecting device which is used in barber shops to remove hair from barbers' aprons or the like. U.S. Pat. No. 1,934,808 discloses a single-draft fume hood for use in chemical laboratories and other places where more or less noxious or disagreeable fumes are developed in the course of chemical operations. U.S. Pat. No. 1,977,386 discloses a work hood to cover articles or workpieces which is connected to a central vacuuming and collection system for the entire shop area. U.S. Pat. No. 4,637,301 is directed to a contamination control work station for use when working on radioactive or other toxic or hazardous materials to prevent the release of contaminated and toxic gases and particles to the atmosphere.